shrinking linux guest disks mount error

[Kevin666]

As many have there are plenty of internet instructions on how to use zerofree to shrink your guest disks but I am having a problem with mine being able to unload the disk and remount in read only mode so I do :-

Code: Select all

mount -n -o remount,ro -t ext4 /dev/sda1 /

it thinks about and then comes back with :-

Code: Select all

mount: / is busy

so anybody got any reason why or am i missing something

have used dd instead but there are some issues apparently with it and zerofree has been given the thumbs up

TIA

[fixedwheel]

man zerofree

To remount the root file-system readonly, you can first switch to single user runlevel (telinit 1) then use mount -o remount,ro filesystem.